Mixtures of alkylated methylolated 4,5-dihydroxy-imidazolidin-2-ones

ABSTRACT

Described is a process for preparing mixtures of mixed-alkylated methylolated 4,5-dihydroxyimidazolidin-2-ones by reaction of methylolated 4,5-dihydroxyimidazolidin-2-one (DMDHEU) with a monohydric C 1-5  alcohol and a polyol selected from the group consisting of ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, glycerol and polyethylene glycols of the formula HO(CH 2 CH 2 O) n H where 3≦n≦20, the monohydric C 1-5  alcohol and the polyol each being used in an amount of from 0.1 to 2.0 mol equivalents, based on DMDHEU, and the reaction being carried out at temperatures from 20° C. to 70° C. and at a pH of from 1 to 2.5, and the pH being set to a value of from 4 to 8 after the reaction.

This application is a 371 of PCT/EP97/07318 filed Dec. 30, 1997.

The present invention relates to mixtures of mixed-alkylatedmethylolated 4,5-dihydroxyimidazolidin-2-ones. The invention alsorelates to a process for preparing the mixtures mentioned, to finishingbaths thereof and to their use.

Methylolated 4,5-dihydroxyimidazolidin-2-ones are used in textilefinishing as low-formaldehyde textile crosslinkers. They are alsodescribed as DMDHEU compounds (cf. Ullmann's Encyclopedia of IndustrialChemistry, Vol. A 26, pages 227 to 350]. These textile crosslinkers areeffective for good crease recovery and reduced textile shrinkage. AndDMDHEU derivatives reacted with methanol provide good easy-care effects.At the same time, the formaldehyde contents of the textiles treated withsuch DMDHEU derivatives are low. Yet there are disadvantages in the formof high emissions in use, i.e. in textile finishing, due to residualmethanol or partly detached methanol.

U.S. Pat. No. 4,396,391 discloses the treatment of cellulosic textileswith polyol-derivatized DMDHEU. The DMDHEU reacted with polyols or theirmixtures leads to low formaldehyde values in the treatment of textiles.However, the disadvantage of these hydroxyalkoxyalkylated DMDHEUderivatives is that their easy-care effects are inferior tomethanol-derivatized DMDHEU compounds.

It is an object of the present invention to provide a low-formaldehydetextile crosslinker which provides good finishing effects with lowformaldehyde values on the textile coupled with low emissions in textilefinishing use. It shall impair the breaking strength of the fiber aslittle as possible, if at all, and confer good smoothness on it. Inaddition, it shall provide good easy-care effects.

This object is achieved by mixtures of mixed-alkylated methylolated4,5-dihydroxyimidazolidin-2-ones, which are preparable by reaction ofmethylolated 4,5-dihydroxyimidazolidin-2-one (DMDHEU) with a monohydricC₁₋₅ alcohol and a polyol selected from the group consisting of ethyleneglycol, diethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol,1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, glyceroland polyethylene glycols of the formula HO(CH₂CH₂O)_(n)H where 3=n=20,the monohydric C₁₋₅ alcohol and the polyol each being used in an amountof from 0.1 to 2.0 mol equivalents, based on DMDHEU, and the reactionbeing carried out at temperatures from 20° C. to 70° C. and at a pH offrom 1 to 2.5, and the pH being set to a value of from 4 to 8 after thereaction.

The invention further provides a corresponding process for preparingthese mixtures. The invention additionally provides an aqueous finishingbath for cellulosic textile materials, which comprises the said mixturesof the invention.

In the mixtures provided according to the invention, DMDHEU preferablyhas asymmetric substitution on the two nitrogen atoms of theimidazolidine ring. It is preferred for one of the two methylol groupsof DMDHEU to be etherified with a methyl radical and the other methylolgroup to be derivatized by reaction with a polyol selected from thegroup consisting of ethylene glycol, diethylene glycol, 1,2-propyleneglycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol,1,4-butylene glycol, glycerol and polyethylene glycols of the formulaHO(CH₂CH₂O)_(n)H where 3≦n≦20, preferably diethylene glycol.

The mixtures of such asymmetrically substituted DMDHEU derivatives andtheir aqueous solutions are useful in textile finishing aslow-fornaldehyde textile crosslinkers because they have very lowformaldehyde values. At the same time, the emissions in textilefinishing are likewise reduced. In addition, the strength of thecellulosic textile materials treated therewith is distinctly improved aswell. Another aspect is that the Monsanto smoothness image showsimproved values.

The novel process for preparing the mixtures has both a single-stage anda two-stage variant. In the two-stage variant, an aqueous solution ofDMDHEU is initially reacted with a monohydric C₁-C₅-alkohol, preferablymethanol. From 0.1 to 2.0 mol equivalents of the alcohol are used. ThepH during the reaction is within the range from 1 to 2.5. Thetemperature is from 20° C. to 70° C. The DMDHEU solution used has asolids content of typically 40-85% by weight. The reaction takes placein the presence of mineral acids, mixtures thereof or organic acids.Preferred acids are phosphoric acid or its mixtures with other mineralacids. The reaction times are within the range from 0.5 to 6 hours.

After this first reaction step, the aqueous solution is reacted in asecond step with again from 0.1 to 2.0 mol equivalents of a polyolselected from the group consisting of ethylene glycol, diethyleneglycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol,1,3-butylene glycol, 1,4-butylene glycol, glycerol and polyethyleneglycols of the formula HO(CH₂CH₂O)_(n)H where 3≦n≦20. Preferably, themonohydric C₁₋₅ alcohol is used in an amount of from 0.7 to 2.0 molequivalents and the polyol in an amount of from 0.8 to 1.4 molequivalents, each based on DMDHEU. Preferably, the monohydric C₁₋₅alcohol and the polyol are altogether used in an amount of from 1.7 to2.9 mol equivalents, based on DMDHEU. The pH and the temperature of thereaction of the second step are within the ranges already mentioned inconnection with the first step. Diethylene glycol is the preferredpolyol. The order of the first process step and the second process stepare advantageously changed. After the reaction has ended, the pH isadjusted to 4-8 by means of a customary base, for example sodiumhydroxide or potassium hydroxide. The resulting solutions are adjustedto a desired solids content within the range from 40 to 85% by weight.

The novel mixtures can also be prepared in a single-stage process byreaction of aqueous solutions of DMDHEU with alcohol mixtures. Herealcohol mixtures are mixtures of the abovementioned alcohol components,namely of the monohydric C₁-C₅-alcohols and the polyols mentioned. Themixtures mentioned contain the monohydric C₁-C₅-alcohols and the polyolswhich are used according to the invention in ratios of 0.1-2.0:2.0-0.1mol equivalents. The reaction takes place at a pH of from 1 to 2.5 andat from 20 to 70° C., preferably 20 to 50° C., in the presence ofmineral acids, mixtures thereof or organic acids. The single-stagereaction is preferably carried out in the presence of phosphoric acid orits mixtures with other mineral acids. As with the two-stage reaction,the pH is adjusted to 4-8 by means of a customary base, for examplesodium hydroxide or potassium hydroxide, after the reaction has ended.The preferred C₁-C₅-alcohol for the single-stage process is againmethanol. And the preferred polyol is again diethylene glycol.

As already mentioned, the mixtures according to the invention are usedfor finishing cellulosic textile materials. Cellulosic textile materialsare finished using a finishing bath which contains the mixturesaccording to the invention together with other, customary constituents,e.g. catalysts such as magnesium chloride, for example.

The Examples which follow illustrate the invention.

PREPARATION EXAMPLES Inventive Example 1

To 116 parts of an aqueous methylolated 4,5-dihydroxyimidazolidin-2-onesolution having a solids content of 70% by weight were added 16 parts ofmethanol. The pH was adjusted to a value within the range from 1.3 to2.4 using 5 parts of phosphoric acid, and the alkylation was thencarried out at 50° C. for 1.5 h. 58 parts of diethylene glycol were thenadded, and the second alkylation stage was carried out at 50° C. Afterabout 1.5 h the reaction solution was cooled down and adjusted to pH 5and to a solids content of 70% by weight.

Inventive Example 2

Inventive Example 1 was repeated, except that the order of the reactionswith diethylene glycol and methanol was changed.

Inventive Example 3

To 239 parts of an aqueous methylolated 4,5-dihydroxyimidazolidin-2-onesolution having a solids content of 68% by weight were added 127 partsof diethylene glycol. The pH was adjusted to a value within the rangefrom 1.2 to 2.4 using a mixture of phosphoric acid and sulfuric acid,and the etherification was then carried out at 50° C. for 1 h. 26 partsof methanol were then added; the second etherification stage was carriedout at 50° C. After about 1 h the reaction solution was cooled down andadjusted to pH 5 and a solids content of 69% by weight.

Inventive Example 4

To 130 parts of an aqueous methylolated 4,5-dihydroxyimidazolidin-2-onesolution having a solids content of 75% by weight were added 83 parts ofdiethylene glycol. The pH was adjusted to a value within the range from1.2 to 2.4 using phosphoric acid, and then the etherification wascarried out at 50° C. for 1 h. Thereafter 10 parts of methanol wereadded, and the second etherification stage was carried out at 50° C.After about 1 h the reaction solution was cooled down and adjusted to apH of 5 and a solids content of 71% by weight.

Inventive Example 5

To 178 parts of an aqueous methylolated 4,5-dihydroxyimidazolidin-2-onesolution having a solids content of 74% by weight were added 49 parts ofmethanol and 59 parts of diethylene glycol. The pH was adjusted to avalue within the range from 1.3 to 2.4 using phosphoric acid, and thenthe etherification was carried out at 50° C. for 2 h. After the reactionhad ended, the mixture was cooled down and adjusted to pH 5 and to asolids content of 70% by weight.

Comparative Example 1

An etherified product prepared under standard conditions from aqueousmethylolated 4,5-dihydroxyimidazolidin-2-one solution and methanol.

Comparative Example 2

A product alkylated from aqueous methylolated4,5-dihydroxyimidazolidin-2-one solution and methanol under standardconditions and admixed with diethylene glycol.

Comparative Example 3

An etherified product prepared under standard conditions from aqueousmethylolated 4,5-dihydroxyimidazolidin-2-one solution and diethyleneglycol.

Application Testing

a) Treatment of Test Fabrics

The products were used to prepare a 4% strength solution (based on 100%solids) additionally comprising 1.2% of magnesium chloride crystals ascatalyst. The test fabric (cotton) was impregnated with these solutionsin a pad-mangle to a wet pickup of 75%. It was then dried at 120° C. toa residual moisture content of 6-8%. Curing took place at 150° C. over 4min.

b) Test Results

Breaking Emission factor g of LAW 112 Monsanto loss C/kg of Example ppmrating md in % product** Inventive 4 48 3 19 2 Inventive 3 87 2.5 16 2Inventive 2 31 3 25 3 Inventive 1 36 2.8 22 4 Comparative 1 73 3.3 33 15Comparative 2 46 3 28 11 Comparative 3 48 2 20 1 * compared withuntreated cotton ** measured by FID method

We claim:
 1. A process for preparing a mixture of mixed-alkylated methylolated 4,5-dihydroxyimidazolidin-2-ones, comprising: reacting methylolated 4,5-dihydroxyimidazolidin-2-one (DMDHEU) with a monohydric C₁₋₅ alcohol and a polyol selected from the group consisting of ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, glycerol, and polyethylene glycols of the formula HO(CH₂CH₂O)_(n)H, wherein 3≦n≦20, wherein the monohydric C₁₋₅ alcohol and the polyol are each used in an amount of from 0.1 to 2.0 mol equivalents, based on the DMDHEU, and the reaction is conducted at a temperature from 20° to 70° C. and at a pH of from 1 to 2.5, followed by setting the pH to a value of from 4 to 8 after the reaction, wherein said mixture contains mixed-alkylated DMDHEUs which are asymmetrically substituted on the two nitrogen atoms of the imidazoline ring of the DMDHEU.
 2. A process as claimed in claim 1, wherein said reacting is conducted in one or two stages.
 3. A process as claimed in claim 1, wherein the monohydric C₁-C₅-alcohol is methanol and the polyol is diethylene glycol.
 4. A process as claimed in claim 1, wherein said reacting is conducted at a temperature from 20 to 50° C.
 5. A process as claimed in claim 1, wherein the monohydric C₁-C₅-alcohol is used in an amount of from 0.7 to 2.0 mol equivalents and the polyol is used in an amount of from 0.8 to 1.4 mol equivalents, based on the DMDHEU.
 6. A process as claimed in claim 1, wherein the total amount of the monohydric C₁₋₅ alcohol and the polyol used is from 1.7 to 2.9 mol equivalents, based on DMDHEU. 